Hinge structure

ABSTRACT

An integral hinge assembly for a plastic container having a base and a lid constructed to permit the lid to be assembled to the base by sliding it axially in position with one motion, wherein the base includes spaced aligned bosses having cylindrical bearing surfaces with one of the bosses being slotted to receive the lid during assembly. The lid has integrally formed therewith a central shank portion flanked by two oppositely directed pintles with the pintle leading during assembling having a smaller diameter than the other pintle to form a shoulder with the shank portion limiting the movement of the pintles into the bosses during assembly. There is also provided, adjacent what would be the trailing pintle during assembly, a frusto-conical portion between the pintles that cams the slotted boss open somewhat as it passes therethrough and after passing therethrough permits the slotted boss to clamp around the larger pintle with the shoulder formed by the frusto-conical portion preventing the disassembly of the lid by withdrawal in the opposite direction.

United States Patent 91 De Groft f 1 Jan.16, 1973 [54] HINGE STRUCTURE [75] Inventor: Walter J. De Groft, Glen Ellyn, Ill. [73] Assignee: Sanford Research Company [22] Filed: Feb. 9, 1971 [21] Appl. No.: 113,997

52 user ..l6/l7l,220/3l,16/176, 16/178,16/169 [51] Int.Cl. ..E05dl/06 [58] Field of Search, ..16/l71, 169, 168,176, 175, 16/178; 220/31 R, 31 SR Primary Examiner-Bobby R. Gay

Assistant Examiner-Doris L. Troutman Attorneyl-lofgren, Wegner, Allen, Stellman & Mc- Cord [57] ABSTRACT An integral hinge assembly for a plastic container having a base and a lid constructed to permit the lid to be assembled to the base by sliding it axially in position with one motion, wherein the base includes spaced aligned bosses having cylindrical bearing surfaces with one of the bosses being slotted to receive the lid during assembly. The lid has integrally formed therewith a central shank portion flanked by two oppositely directed pintles with the pintle leading during assembling having a smaller diameter than the other pintle to form a shoulder with the shank portion limiting the movement of the pintles into the bosses during assembly. There is also provided, adjacent what would be the trailing pintle during assembly, a frusto-conical portion between the pintles that cams the slotted boss open somewhat as it passes therethrough' and after passing therethrough permits the slotted boss to clamp around the larger pintle with the shoulder formed by the frusto-conical portion preventing the disassembly of the lid by withdrawal in the opposite direction.

4 Claims, 4 Drawing Figures BACKGROUND OF THE PRESENT INVENTION The present invention relates to hinge constructions for small plastic containers and more particularly to a rugged inexpensive hinge that is simple to mold yet easy to assemble.

There have in the past been provided hinges consisting of spaced bosses on one of the hinge elements and corresponding spaced pintles on the other of the hinge elements with one of the bosses being slotted to permit the axial insertion of the pintle carrying hinge element through the boss to permit axial assembly. These prior hinge constructions, however, have been multiple part hinges requiring a plurality of steps during assembly and also requiring significant machining operations.

More specifically, prior hinge constructions of the axial assembly type have required a threaded member on one of the pintles to prevent over-insertion of the pintles into the bosses. Moreover, many prior constructions have required the threading of a stop member on the leading pintle after assembly to prevent removal of the pintle assembly from the bosses.

These additional stop elements require not only separate fabrication and machining, but represent additional assembly steps that must be performed during assembly operation.

It is a primary object of the present invention to overcome the problems of prior art axial assembly hinge constructions.

SUMMARY OF THE PRESENT INVENTION In accordance with the present invention a hinge construction or assembly is provided integrally molded with a plastic container. The pintles and the pintle retaining elements are all integrally molded with the lid while the bosses are integrally molded with the container base obviating the necessity for separate hinge retaining elements characteristic of the prior art. The container base has integrally molded therewith a pair of spaced, aligned bosses, one having a larger diameter than the other and being slotted to receive the container lid during axial assembly. The lid has integrally molded therewith a central shank portion having a diameter approximating that of the larger boss with a pair of oppositely directed pintles, one having a large diameter adapted to be received in a larger boss and the other having a smaller diameter adapted to be received in the smaller boss.

During assembly the lid is assembled to the container base by axially inserting the smaller pintle through the larger boss, permitting the web interconnecting the shank with the lid to pass through the slot in the larger boss. After the shank passes through the larger boss a frusto-conical camming portion at the end of the shank adjacent the larger pintle expands the larger slotted boss somewhat permitting the frusto-conical portion to pass therethrough. After it passes through the larger boss the boss clamps, around the larger pintle and the frusto-conical portion defines a shoulder preventing the withdrawal of the pintles from the bosses. To prevent the overinsertion of the pintles during assembly, the smaller diameter pintle forms a shoulder with the shank that engages the smaller diameter boss and limits the axial insertion of the pintles during the forward assembly motion.

This novel hinge construction provides an extremely rugged assembly, even though constructed of plastic, since no fragile parts need to be employed. One of the basic advantages of this hinge construction is that it eliminates weak points of and in small and brittle diameters in prior constructions where they connect the hinge to the body of the base and the lid. Moreover, the configuration of the hinge elements significantly reduces the molding costs. Because all of the retaining elements are integrally formed with the pintle assembly, the lid slides and locks into place with one motion reducing the assembly cost.

Since the container is molded in two separate parts the lid and the base may be constructed of plastics having different colors or properties as desired.

BRIEF DESCRIPTION OF THE DRAWING DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawing, a two piece molded plastic container 10 is seen to consist of a lid member 11 and a base 12, interconnected by a hinge assembly 13 having parts molded integrally with the lid and base.

The base is a one piece molded member and consists of a bottom wall 15, side walls 16 and 17, and front and rear walls 19 and 20. t

The rear wall 20 has projecting rearwardly therefrom bosses 22 and 24 aligned and having through bores 26 and 27 therein as shown more clearly in FIG. 3. Boss 22 is slotted as indicated at 29 so that it is resiliently deformable and bore 26 is larger than bore 27 to provide a retaining function as will appear herein.

The lid 11 has a web portion 32 interconnected with a shank portion 34 having a diameter approximating the diameter of bore 26, but slightly smaller so that the shank portion may be readily received within the bore 26 during assembly.

Projecting from what is the leading end of the lid dur-v ing assembly is a smaller diameter pintle 36 having a diameter sufficient to be snuggly, but easily rotatable within bore 27 in boss 24. Extending from the trailing end of the shank portion 34 is a larger diameter pintle 38 having a sufficient diameter to be snuggly received but easily rotatable in bore 26 of boss 22.

For the purpose of limiting the assembling movement of the pintles into the bosses 22 and 24, a shoulder 40 is defined between the shank portion 34 and the small pintle 36, with the shoulder 40 engaging side 41 of boss 24.

To prevent withdrawal of the lid 11 from the base after assembly, a frusto-conical portion 44 is provided at the trailing end of the shank 34 having an outer diameter approximately 0.010 inches greater at its largest point than the interior diameter of bore 26 when boss 22 is relaxed. The frusto-conical portion 44 defines a shoulder 46 that engages side 48 of boss 22 preventing the withdrawal of the lid and pintles from the bosses after the assembly movement has been completed. Shoulder 46 is spaced from shoulder 40 a distance slightly less than the spacing between the boss sides 41 and 48.

After the container, base and lid have been molded and preparatory to assembly, the axis of the pintles 36 and 38 is aligned with the bores 27 and 26 as shown in FIG. 2. The lid is then moved along this axis designated 50 in FIG. 2, inserting the small pintle 36 through bore 26. This movement is continued with the shank portion 34 passing through bore 26 while the web portion 32 passes through slot 29 in boss 22.

When frusto-conical portion 44 engages the left end of bore 26, it cams the boss 22 open somewhat permitting the projection 44 to pass through the bore, after the projection 44 passes completely through the bore, the boss 22 contracts around and engages the larger pintle 38. This collapse of the boss 22 around the pintle activates shoulder 46 so that it engages side 48 of boss 22 and prevents withdrawal.

Just after the projection 44 releases the boss 22 in the rightward movement of the lid as shown in FIG. 3, shoulder 40 engages side 41 and limits the motion of the lid in the assembly direction.

I claim:

1. A hinge assembly, comprising: a first hinge member having a first boss with a bearing surface therein, a second boss on said first hinge member having a bearing surface therein generally aligned with the bearing surface in the first boss, a second hinge member rotatable relative to said first hinge member and insertable in said first member during assembly generally axially of said bosses, said second hinge member having a first pintle axially slidable in said first boss during assembly, said first pintle having a shoulder portion larger in diameter than said first boss bearing surface so that the shoulder engages the boss and limits movement of the first pintle into the first boss, a second pintle on said second hinge member insertable axially in said second boss, slot means in said second boss permitting axial insertion of the second hinge member, and means preventing the axial withdrawal of the second hinge member relative to the first hinge member, said means preventing axial withdrawal of the second hinge member including a flange integral with said second pintle and engageable with said second boss. 2

2. A hinge assembly comprising: a first hinge member having a first boss with a bearing surface therein, a second boss on said first hinge member having a bearing surface therein generally aligned with the bearing surface in the first boss, a second hinge member rotatable relative to said first hinge member and insertable in said first member during assembly generally axially of said bosses, said second hinge member having a first pintle axially slidable in said first boss during assembly, said first pintle having a shoulder portion larger in diameter than said first boss bearing surface so that the shoulder engages the boss and limits movement of the first pintle into the first boss, a second pintle on said second hinge member insertable axially in said second boss, slot means in said second boss permitting axial insertion of the second hinge member, and means preventing the axial withdrawal of the second hinge member relative to the first hinge member, wherein said means for preventing withdrawal of the second hinge member relative to said first hinge member includes a frusto-conical shoulder adjacent said second pintle for camming the second boss open during assembly to permit insertion of said latter shoulder.

3. A hinge construction for a container having a base and a lid, comprising: first and second generally annular spaced and aligned bosses on the base member, said bosses having aligned bosses therethrough with the base of the first boss being smaller in diameter than the base of the second boss, a radially extending slot in said second boss, first and second aligned pintles on said lid, a shank portion integrally formed with and extending between said pintles, said first pintle being received in said first boss, said second pintle having a larger diameter and being received in said second boss, said shank portion being larger in diameter than said first pintle and defining a shoulder for limiting the axial insertion of the first pintle into the first boss as the lid is assemblied to the base, and means for preventing withdrawal of the pintles from the bosses after assembly including an integral cam on the shank portion having a sufficient diameter to open the second boss during insertion and spaced from said shoulder a distance to engage the second boss after assembly when the second boss closes around the second pintle.

4. A hinge construction as defined in claim 2,

wherein said cam is a frusto-conical portion on the end of the shank portion adjacent the second boss.

UNr r EDSTATEs PATENT AND "IRADEMARK O FFiCE CERTIFICATE OF CORRECTION Q PATENT NO. 1 3,710,419

DATED Januar 16, 1973 INVENTOR(S) Walter J. De Graft It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 4, line 45, "2" should he --3 Signed and Sealed this Second D a) of January I 979 [SEAL] A um.-

RUTH MASON DONALD w. BANNER Arresting Oflier Commissionef of Patents and T rademrks 

1. A hinge assembly, comprising: a first hinge member having a first boss with a bearing surface therein, a second boss on said first hinge member having a bearing surface therein generally aligned with the bearing surface in the first boss, a second hinge member rotatable relative to said first hinge member and insertable in said first member during assembly generally axially of said bosses, said second hinge member having a first pintle axially slidable in said first boss during assembly, said first pintle having a shoulder portion larger in diameter than said first boss bearing surface so that the shoulder engages the boss and limits movement of the first pintle into the first boss, a second pintle on said second hinge member insertable axially in said second boss, slot means in said second boss permitting axial insertion of the second hinge member, and means preventing the axial withdrawal of the second hinge member relative to the first hinge member, said means preventing axial withdrawal of the second hinge member including a flange integral with said second pintle and engageable with said second boss.
 2. A hinge assembly comprising: a first hinge member having a first boss with a bearing surface therein, a second boss on said first hinge member having a bearing surface therein generally aligned with the bearing surface in the first boss, a second hinge member rotatable relative to said first hinge member and insertable in said first member during assembly generally axially of said bosses, said second hinge member having a first pintle axially slidable in said first boss during assembly, said first pintle having a shoulder portion larger in diameter than said first boss bearing surface so that the shoulder engages the boss and limits movement of the first pintle into the first boss, a second pintle on said second hinge member insertable axially in said second boss, slot means in said second boss permitting axial insertion of the second hinge member, and means preventing the axial withdrawal of the second hinge member relative to the first hinge member, wherein said means for preventing withdrawal of the second hinge member relative to said first hinge member includes a frusto-conical shoulder adjacent said second pintle for camming the second boss open during assembly to permit insertion of said latter shoulder.
 3. A hinge construction for a container having a base and a lid, comprising: first and second generally annular spaced and aligned bosses on the base member, said bosses having aligned bosses therethrough with the base of the first boss being smaller in diameter than the base of the second boss, a radially extending slot in said second boss, first and second aligned pintles on said lid, a shank portion integrally formed with and extending between said pintles, said first pintle being received in said first boss, said second pintle having a larger diameter and being received in said second boss, said shank portion being larger in diameter than said first pintle and defining a shoulder for limiting the axial insertion of the first pintle into the first boss as the lid is assemblied to the base, and means for preventing withdrawal of the pintles from the bosses after assembly including an integral cam on the shank portion having a sufficient diameter to open the second boss during insertion and spaced from said shoulder a distance to engage the second boss after assembly when the second boss closes around the second pintle.
 4. A hinge construction as defined in claim 2, wherein said cam is a frusto-conical portion on the end of the shank portion adjacent the second boss. 